Japan's Nikkei newspaper's website said Japanese Foreign Minister Koichiro Gemba received the assurance during a meeting with his Emirati counterpart during a visit to the Gulf state.

Sheikh Abdullah bin Zayed Al-Nahyan was quoted as saying that the UAE "will deliver it (oil) in a stable manner."

Gemba has been visiting key Gulf oil producers.

His trip coincides with concerns that Iran might try to close the strait in retaliation for new US sanctions on its central bank.

The sanctions would make it difficult for Iran to sell its crude.